我有一个网站。 我的网站根目录的语言部分：
location ~ ^/(ar|en|es|pl) { rewrite ^/(.*)(/+)$ /$1 permanent; root /var/www/mysite.com/cache/webpages; try_files $uri.html /index.php?path=$uri; } 例如，我已经看到这个：
set_from_accept_language $lang en ja pl; where $lang is the variable in which to store the locale and en ja pl are the locales supported by the website. If none of the locales from accept_language is available on your website, the variable (here, $lang) is set to the first locale in the list (here, en).
从https://www.nginx.com/resources/wiki/modules/accept_language/
好吧，我试图用这个：
set_from_accept_language $lang ar en es pl; location ~ ^/ { rewrite ^/(.*)(/+)$ /$lang permanent; root /var/www/mysite.com/cache/webpages; try_files $uri.html /index.php?path=$uri; }
结果我收到错误：
Starting nginx: nginx: [emerg] variable already defined: "lang" in /etc/nginx/mysite.conf:58
也许我不明白的东西，你能帮助我，如何解决这个问题？ 如何将语言列表分配给variables？